Electrochemical dechlorination of trichloroethylene in the presence of natural organic matter, metal ions and nitrates in a simulated karst media

Fallahpour, N; Mao, X; Rajic, L; Yuan, S; Alshawabkeh, AN

HERO ID

4453520

Reference Type

Journal Article

Year

2017

Language

English

PMID

29744302

HERO ID 4453520
In Press No
Year 2017
Title Electrochemical dechlorination of trichloroethylene in the presence of natural organic matter, metal ions and nitrates in a simulated karst media
Authors Fallahpour, N; Mao, X; Rajic, L; Yuan, S; Alshawabkeh, AN
Journal Journal of Environmental Chemical Engineering
Volume 5
Issue 1
Page Numbers 240-245
Abstract A small-scale flow-through limestone column was used to evaluate the effect of common coexisting organic and inorganic compounds on the electrochemical dechlorination of trichloroethylene (TCE) in karst media. Iron anode was used to produce ferrous ions and promote reducing conditions in the column. The reduction of TCE under 90 mA current, 1 mL min-1 flow rate, and 1 mg L-1 initial TCE concentration, was inhibited in the presence of humic acids due to competition for direct electron transfer and/or reaction with atomic hydrogen produced at the cathode surface by water electrolysis. Similarly, presence of 10 mg L-1 chromate decreased TCE reduction rate to 53%. The hexavalent chromium was completely reduced to trivalent chromium due to the ferrous species produced from iron anode. Presence of 5 mg L-1 selenate decreased the removal of TCE by 10%. Chromium and selenate complexation with dissolved iron results in formation of aggregates, which cover the electrodes surface and reduce TCE dechlorination rate. Presence of 40 mg L-1 nitrates caused reductive transformation of TCE up to 80%. Therefore, TCE removal is influenced by the presence of other contaminants that are present as a mixture in groundwater in the following order: humic acid, chromate, selenate, and nitrate.
Doi 10.1016/j.jece.2016.11.046
Pmid 29744302
Wosid WOS:000398950800027
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English